An intuitive interaction method easy to understand is being recently used in combination with an augmented reality (AR), a virtual reality, and gesture recognition, in various application fields such as game machines, televisions (TVs), mobile terminals, wearable computers, etc. However, since most of methods use a physical touch panel or a physical user interface (PUI) at present, a user should actually touch a button, or touch or hold specific equipment. To overcome such a limitation, much research interests in a method in which a product interacts with a hand in a space. In particular, wearable equipment that enables the free use of both hands as in Google Glass requires an interaction method using an arm/hand.